Electronic circuit cards, including non-volatile memory cards, have been commercially implemented according to a number of well-known standards. Memory cards are used with personal computers, cellular telephones, personal digital assistants (PDAs), digital still cameras, digital movie cameras, portable audio players and other host electronic devices for the storage of large amounts of data. Such cards usually contain a re-programmable non-volatile semiconductor memory cell array along with a controller that controls operation of the memory cell array and interfaces with a host to which the card connected. Several of the same type of card may be interchanged in a host card slot designed to accept that type of card. However, the development of the many electronic card standards has created different types of cards that are incompatible with each other in various degrees. A card made according to one standard is usually not useable with a host designed to operate with a card of another standard.
One such standard, the PC Card Standard, provides specifications for three types of PC Cards. Originally released in 1990, the PC Card Standard now contemplates three forms of a rectangular card measuring 85.6 mm. by 54.0 mm., having thicknesses of 3.3 mm. (Type I), 5.0 mm. (Type II) and 10.5 mm. (Type III). An electrical connector, which engages pins of a slot in which the card is removably inserted, is provided along a narrow edge of the card. PC Card slots are included in current notebook personal computers, as well as in other host equipment, particularly portable devices. The PC Card Standard is a product of the Personal Computer Memory Card International Association (PCMCIA). The current PC Card specifications, “PC Card Standard Release 8.0,” dated April 2001, is available from the PCMCIA.
In 1994, SanDisk Corporation, assignee of the present application, introduced the CompactFlash™ card (CF™ card) that is functionally compatible with the PC Card but is much smaller. The CF™ card is rectangularly shaped with dimensions of 42.8 mm. by 36.4 mm. and a thickness of 3.3 mm., and has a female pin connector along one edge. The CF™ card is widely used with cameras for the storage of still video data. A passive adapter card is available, in which the CF card fits, that then can be inserted into a PC Card slot of a host computer or other device. The controller within the CF card operates with the card's flash memory to provide an ATA interface at its connector. That is, a host with which a CF card is connected interfaces with the card as if it is a disk drive. Specifications for the CompactFlash card have been established by the CompactFlash Association, “CF+ and CompactFlash Specification Revision 2.0,” dated May 2003. An implementation of these specifications is described by SanDisk Corporation in a product manual “CompactFlash Memory Card Product Manual,” revision 10.1, dated September 2003.
The SmartMedia™ card is about one-third the size of a PC Card, having dimensions of 45.0 mm. by 37.0 mm. and is very thin at only 0.76 mm. thick. Contacts are provided in a defined pattern as areas on a surface of the card. Its specifications have been defined by the Solid State Floppy Disk Card (SSFDC) Forum, which began in 1996. It contains flash memory, particularly of the NAND type. The SmartMedia™ card is intended for use with portable electronic devices, particularly cameras and audio devices, for storing large amounts of data. A memory controller is included either in the host device or in an adapter card in another format such as one according to the PC Card standard. Physical and electrical specifications for the SmartMedia™ card have been issued by the SSFDC Forum.
Another non-volatile memory card is the MultiMediaCard (MMC™). The physical and electrical specifications for the MMC™ are given in “The MultiMediaCard System Specification” that is updated and published from time-to-time by the MultiMediaCard Association (MMCA), including version 3.1, dated June 2001. MMC products having varying storage capacity are currently available from SanDisk Corporation. The MMC card is rectangularly shaped with a size similar to that of a postage stamp. The card's dimensions are 32.0 mm. by 24.0 mm. and 1.4 mm. thick, with a row of electrical contacts on a surface of the card along a narrow edge that also contains a cut-off corner. These products are described in a “MultiMediaCard Product Manual,” Revision 5.2, dated March 2003, published by SanDisk Corporation. Certain aspects of the electrical operation of the MMC products are also described in U.S. Pat. No. 6,279,114 and in patent application Ser. No. 09/186,064, filed Nov. 4, 1998, both by applicants Thomas N. Toombs and Micky Holtzman, and assigned to SanDisk Corporation. The physical card structure and a method of manufacturing it are described in U.S. Pat. No. 6,040,622, assigned to SanDisk Corporation.
A modified version of the MMC™ card is the later Secure Digital (SD) card. The SD Card has the same rectangular size as the MMC™ card but with an increased thickness (2.1 mm.) in order to accommodate an additional memory chip when that is desired. A primary difference between these two cards is the inclusion in the SD card of security features for its use to store proprietary data such as that of music. Another difference between them is that the SD Card includes additional data contacts in order to enable faster data transfer between the card and a host. The other contacts of the SD Card are the same as those of the MMC™ card in order that sockets designed to accept the SD Card can also be made to accept the MMC™ card. A total of nine contacts are positioned along a short edge of the card that contains a cutoff corner. This is described in patent application Ser. No. 09/641,023, filed by Cedar et al. on Aug. 17, 2000, International Publication Number WO 02/15020. The electrical interface with the SD card is further made to be, for the most part, backward compatible with the MMC™ card, in order that few changes to the operation of the host need be made in order to accommodate both types of cards. Complete specifications for the SD card are available to member companies from the SD Association (SDA). A public document describing the physical and some electrical characteristics of the SD Card is available from the SDA: “Simplified Version of: Part 1 Physical Layer Specification Version 1.01,” dated Apr. 15, 2001.
More recently, a miniSD card has been specified by the SDA and is commercially available. This card is smaller than the SD card but provides much of the same functionality. It has a modified rectangular shape with dimensions of 21.5 mm. long, 20.0 mm. wide and 1.4 mm. thick. A total of eleven electrical contacts are positioned in a row on a surface of the card along one edge. The miniSD memory card is available from SanDisk Corporation and described in the “SanDisk miniSD Card Product Manual,” version 1.0, April 2003.
Another type of memory card is the Subscriber Identity Module (SIM), the specifications of which are published by the European Telecommunications Standards Institute (ETSI). A portion of these specifications appear as GSM 11.11, a recent version being technical specification ETSI TS 100 977 V8.3.0 (2000-08), entitled “Digital Cellular Telecommunications System (Phase 2+); Specification of the Subscriber Identity Module—Mobile Equipment (SIM—ME) Interface,” (GSM 11.11 Version 8.3.0 Release 1999). Two types of SIM cards are specified: ID-1 SIM and Plug-in SIM.
The ID-1 SIM card has a format and layout according to the ISO/IEC 7810 and 7816 standards of the International Organization for Standardizaton (ISO) and the International Electrotechnical Commission (IEC). The ISO/IEC 7810 standard is entitled “Identification cards—Physical characteristics,” second edition, August 1995. The ISO/IEC 7816 standard has the general title of “Identification cards—Integrated Circuit(s) Cards with Contacts,” and consists of parts 1-10 that carry individual dates from 1994 through 2000. Copies of these standards are available from the ISO/IEC in Geneva, Switzerland. The ID-1 SIM card is generally the size of a credit card, having dimensions of 85.60 mm. by 53.98 mm., with rounder corners, and a thickness of 0.76 mm. Such a card may have only memory or may also include a microprocessor, the latter often being referred to as a “Smart Card.” One application of a Smart Card is as a debit card where an initial credit balance is decreased every time it is used to purchase a product or a service.
The Plug-in SIM is a very small card, smaller than the MMC™ and SD cards. The GSM 11.11 specification referenced above calls for this card to be a rectangle 25 mm. by 15 mm., with one corner cut off for orientation, and with the same thickness as the ID-1 SIM card. A primary use of the Plug-in SIM card is in mobile telephones and other devices for security against the theft and/or unauthorized use of the devices, in which case the card stores a security code personal to the device's owner or user. In both types of SIM cards, eight electrical contacts (but with as few as five being used) are specified in the ISO/EEC 7816 standard to be arranged on a surface of the card for contact by a host receptacle.
Sony Corporation has developed and commercialized a non-volatile memory card, sold as the Memory Stick™, that has yet another set of specifications. Its shape is that of an elongated rectangle having 10 electrical contacts in a row and individually recessed into a surface adjacent one of its short sides that also contains a cut out corner for orientation. The card's size is 50.0 mm. long by 21.5 mm. wide by 2.8 mm. thick.
A more recent Memory Stick Duo card is smaller, having dimensions of 31.0 mm. long by 20.0 mm. wide by 1.6 mm. thick. Ten contacts are provided in a common recess in a surface and along a short side of the card, which also contains an orienting notch. This smaller card is often used by insertion into a passive adapter having the shape of a Memory Stick card.
SanDisk Corporation has introduced an even smaller transportable non-volatile TransFlash memory module in a modified rectangular shape, having dimensions of 15.0 mm. long by 11.0 mm. wide by 1.0 mm. thick. Eight electrical contact pads are provided in a row on a surface adjacent a short edge of the card. This card is useful for a variety of applications, particularly with portable devices, and is being incorporated into multimedia camera cell telephones.
As is apparent from the foregoing summary of the primary electronic card standards, there are many differences in their physical characteristics including size and shape, in the number, arrangement and structure of electrical contacts and in the electrical interface with a host system through those contacts when the card is connected with a host. Electronic devices that use electronic cards are usually made to work with only one type of card. Adaptors, both active and passive types, have been provided or proposed to allow some degree of interchangeability of electronic cards among such host devices. U.S. Pat. No. 6,266,724 of Harari et al. describes use of combinations of mother and daughter memory cards.
Small, hand-held re-programmable non-volatile memories have also been made to interface with a computer or other type of host through a Universal Serial Bus (USB) connector. These are especially convenient for users who have one or more USB connectors available on the front of their personal computers, particularly if a receptacle slot for one of the above identified memory cards is not present. Such devices are also very useful for transferring data between various host systems that have USB receptacles, including portable devices. Mechanical and electrical details of the USB interface are provided by the “Universal Serial Bus Specification,” revision 2.0, dated Apr. 27, 2000. There are several USB flash drive products commercially available from SanDisk Corporation under its trademark Cruzer. USB flash drives are typically larger and shaped differently than the memory cards described above.
Another, higher transfer rate interface that has become commonplace on personal computers and other host devices is specified by the following standard of the Institute of Electrical and Electronics Engineers (IEEE): “IEEE Standard for a High Performance Serial Bus,” document no. IEEE 1394—1995, as amended by document nos. IEEE 1394a—2000 and IEEE 1394b—2002. A common commercial form of this bus interface is known as FireWire. Because of its higher speed, this interface is particularly useful for the transfer of large amounts of data to and from a computing device.